This release contains tons and tons of bugfixes and security improvements. Credits for this release largely go to Juliette Reinders Folmer aka Jrf / jrfnl.
Also a heartfelt thanks go out to the beta testers who tested all the changes. Special mentions for testers Woyto, Bnpositive, Surbma, DavidCH1, TheITJuggler, kletskater who caught a number of bugs and provided us with actionable information to fix these.
This version also incorporates the SEO Extended plugin functionality into WP SEO with graceful thanks to Faison and Scott Offord for their great work on this plugin.
This version contains a lot of changes under the hood which will break backward compatibility, i.e. once you've upgraded, downgrading will break things.So make sure you make a backup of your settings/database before upgrading.